Volume 22, Issue 2-2, June 2018
CORRELATION BETWEEN DISCHARGE AND WATER QUALITY – CASE STUDY NIŠAVA RIVER (SERBIA)
Authors: Igor Leščešen, Dragosav Pavić, Dragan Dolinaj
Abstract: The water quality and river discharges were surveyed at two sites in Nišava River basin (Dimitrovgrad and Niš) with complete data series for the ten-year period (2005–2014). For these stations SWQI was calculated and correlation analysis was applied. The index value is dimensionless and varies between 0 and 100 (best quality) It is derived from numerous physical, chemical, biological and microbiological parameters. At Niš station average annual value of SWQI is 78 (good) with a clear decrease trend over a ten-year period. On the other side, on Dimitrovgrad station, average annual SWQI is 89 (very good) with a clear positive trend. Goal of this paper was to determine if there is a correlation between river discharge and values of SWQI. Results of the Pearson correlation test between SWQI and daily discharge values for Dimitrovgrad station show a moderate linear relation was observed, r= -0.287, p = 0.002. On Niš station same test has shown that there is no statistically signifcant relation between discharge and water quality (r=0.103 p= 0.297). This study has shown that the correlation between SWQI and discharge is weak or not present at all at the investigated river.
Keywords: Water Quality, Discharge, Nišava River, Serbia
Article info: 97-103
Received: November 19, 2017 | Revised: April 11, 2018 | Accepted: May 02, 2018